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71.
The pancreatic islet tissue of Bufo melanostictus, investigated by differential staining techniques, is generally condensed in the anterior and middle regions, and contains distinguishable islets of various size, shape and or irregular configuration. Histologically, 3 distinct cell types have been identified: B, A1 and A2. Various tinctorial characteristics of B cells reveal that they correspond to the insulin producing B-cells of other vertebrates. The A cells are a few in number, some of which definitely show positive argyrophilia (= A1). A few isolated A- and B-cells are found scattered in the exocrine tissue. A conspicuous feature of several B-cells in some specimens of Bufo melanostictus is the presence of vacuoles of varying size. 相似文献
72.
Efficiency of one- and two-stage selection indexes for improvement of net economic merit in White Leghorns 总被引:2,自引:0,他引:2
V. Ayyagari S. C. Mohapatra G. S. Bisht T. S. Thiyagasundaram D. C. Johari 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1985,71(2):166-171
Summary Mitochondrial (mt) and chloroplast (ct) DNAs from sugar beet lines carrying normal and introduced sources of male sterile cytoplasms have been characterized and compared on the basis of restriction enzyme analysis. Normal cytoplasm was shown to contain mt and ctDNAs which differed from those of the male sterile cytoplasms examined in the present investigation. On the other hand, four groups of male sterile cytoplasms could be differentiated by their own characteristic mtDNA digest patterns, while two were separated by ctDNA comparisons. In addition, a greater degree of variability of the mitochondrial genome is suggested. Our results also imply strict maternal inheritance of mt and ctDNAs. Thus, the organelle DNA assay provides a positive and alternative means of identifying various male sterile cytoplasms. 相似文献
73.
Hanumantharao G. Raj Sangita Gupta Gopa Biswas Suddham Singh Amarjit Singh Amitabh Jha Kirpal S. Bisht Sanjay K. Sharma Subhash C. Jain Virinder S. Parmar 《Bioorganic & medicinal chemistry》1996,4(12):2225-2228
Eighteen 4-methylcoumarins bearing methoxy/hydroxy/acetoxy functionalities have been reported to effectively inhibit the rat liver microsome-mediated aflatoxin B1-DNA binding in vitro. The contribution of functionality on coumarin nucleus towards the inhibition of AFB1-DNA binding is in the order acetoxy> hydroxy> methoxy. The results illustrate the structure-activity relationship. 相似文献
74.
Abhishek Bohra Uday C. Jha Premkumar Adhimoolam Deepak Bisht Narendra P. Singh 《Plant cell reports》2016,35(5):967-993
Key message
A comprehensive understanding of CMS/Rf system enabled by modern omics tools and technologies considerably improves our ability to harness hybrid technology for enhancing the productivity of field crops.Abstract
Harnessing hybrid vigor or heterosis is a promising approach to tackle the current challenge of sustaining enhanced yield gains of field crops. In the context, cytoplasmic male sterility (CMS) owing to its heritable nature to manifest non-functional male gametophyte remains a cost-effective system to promote efficient hybrid seed production. The phenomenon of CMS stems from a complex interplay between maternally-inherited (mitochondrion) and bi-parental (nucleus) genomic elements. In recent years, attempts aimed to comprehend the sterility-inducing factors (orfs) and corresponding fertility determinants (Rf) in plants have greatly increased our access to candidate genomic segments and the cloned genes. To this end, novel insights obtained by applying state-of-the-art omics platforms have substantially enriched our understanding of cytoplasmic-nuclear communication. Concomitantly, molecular tools including DNA markers have been implicated in crop hybrid breeding in order to greatly expedite the progress. Here, we review the status of diverse sterility-inducing cytoplasms and associated Rf factors reported across different field crops along with exploring opportunities for integrating modern omics tools with CMS-based hybrid breeding.75.
We describe a new scaffold-free three-dimensional (3D) cell culture model using cholesteryl ester based lyotropic liquid crystal (LC) substrates. Keratinocytes were deposited randomly on the LC surface where they self-assembled into 3D microtissues or keratinospheroids. The cell density required to form spheroids was optimized. We investigated cell viability using dead/live cell assays. The adhesion characteristics of cells within the microtissues were determined using histological sectioning and immunofluorescence staining. Fourier transform infrared spectroscopy (FTIR) was used to characterize the biochemistry of the keratinospheroids. We found that both cells and microtissues could migrate on the LC surface. The viability study indicated approximately 80% viability of cells in the microtissues up to 20 days of culture. Strong intercellular adhesion was observed in the stratification of the multi-layered microspheroids using field emission-scanning electron microscopy (FE-SEM) and histochemical staining. The cytoskeleton and vinculins of the cells in the microtissues were expressed diffusely, but the microtissues were enriched with lipids and nucleic acids, which indicates close resemblance to the conditions in vivo. The basic 3D culture model based on LC may be used for cell and microtissue migration studies in response to cytochemical treatment. 相似文献
76.
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78.
Polyhydroxyalkanoates (PHAs) are biodegradable polymers produced by microbes to overcome environmental stress. Commercial
production of PHAs is limited by the high cost of production compared to conventional plastics. Another hindrance is the brittle
nature and low strength of polyhydroxybutyrate (PHB), the most widely studied PHA. The needs are to produce PHAs, which have
better elastomeric properties suitable for biomedical applications, preferably from inexpensive renewable sources to reduce
cost. Certain unique properties of Bacillus subtilis such as lack of the toxic lipo-polysaccharides, expression of self-lysing genes on completion of PHA biosynthetic process
– for easy and timely recovery, usage of biowastes as feed enable it to compete as potential candidate for commercial production
of PHA. 相似文献
79.
Sheran HW Law Rudolf SS Wu Patrick KS Ng Richard MK Yu Richard YC Kong 《BMC molecular biology》2006,7(1):15-13
Background
Hypoxia-inducible factors (HIFs) are involved in adaptive and survival responses to hypoxic stress in mammals. In fish, very little is known about the functions of HIFs. 相似文献80.
Subhash C. Joshi Rajendra C. Padalia Dinesh S. Bisht Chandra S. Mathela 《化学与生物多样性》2009,6(9):1364-1373
The leaf terpenoid compositions of nine Lauraceae species, viz., Neolitsea pallens, Lindera pulcherrima, Dodecadenia grandiflora, Persea duthiei, Persea odoratissima, Persea gamblei, Phoebe lanceolata, Cinnamomum tamala, and Cinnamomum camphora, collected from the Himalayan region (India) were examined by GC, GC/MS, and NMR analyses in order to determine the similarities and differences among their volatile constituents. Furano‐sesquiterpenoids were the principal constituents of N. pallens, L. pulcherrima, and D. grandiflora. (E)‐Nerolidol, limonene, β‐pinene, and α‐pinene were the major constituents of P. duthiei; α‐pinene, sabinene, and β‐caryophyllene were predominant in P. odoratissima, while the oils of P. gamblei and P. lanceolata possessed β‐caryophyllene as common major constituent. C. camphora and C. tamala were marked by the presence of camphor and cinnamaldehyde, respectively. Cluster analysis of the oil composition was carried out in order to discern the differences and similarities within nine species of six genera of Lauraceae. 相似文献